Sailboats use wind to move forward in the water. As such, a sailboat must balance the forces of air pressure on the sails against water pressure on the hull(s) to efficiently move the boat in a given direction. This balance, or stability, is achieved using a variety of methods and designs.
In the case of a single-hull sailboat, or monohull, stability is achieved primarily through the use of a ballasted keel which lowers the center of gravity. In lowering the center of gravity, the righting-moment on a monohull is located between the center of gravity and the center of buoyancy on the hull. To support the weight of the ballast, the hull of a monohull is made wider which also increases stability.
In the case of a multi-hull sailboat, such as a catamaran or trimaran, stability is achieved primarily through extending the distance between the two hulls of a catamaran and/or the three hulls of a trimaran. A multihull therefore does not make use of a ballasted keel. The stability of a multihull is entirely dependent on the boat's overall width (beam) and the shape of the hulls.
While multihulls achieve the goal of sustaining sufficient stability under normal conditions of use, their respective width make them difficult and costly to transport and store. Highway rules make transporting a trimaran wider then 8′6″ via a trailer unfeasible. The hull sizes for these watercrafts also tend to increase their manufacturing costs and hence, a greater cost to the consumer.
Boats having relatively narrow hulls and including features to enhance stability have heretofore been known. Typical prior art related to such boats is shown in U.S. Pat. Nos. 4,954,357; 5,647,294; 5,682,831; 5,642,682; 5,515,801; 5,771,715; 4,664,049; 4,512,275; 4,562,785; 4,730,570 and 5,174,233. Boats having narrow central hulls are particularly unstable; however, such boats are normally relatively easy to transport and relatively light in weight. Rigid or fixed laterally-mounted stabilizers for watercraft are known in the art, but such rigs are difficult to transport over land and to store when not in use. Accordingly, it is an object of the present invention to provide a watercraft having stabilizers which are selectively extendible and retractable relative to the hull of the watercraft.
Another object of the invention is to provide a watercraft having selectively adjustable elongated floatation members which provide lateral (side to side) stability while at the same time proving longitudinal (fore to aft) stability.